Originally Posted by david 335is
Its 2012, 2012 335is kept the N54
It was between the new redesigned 2012 335i or 2012 335is. It was a tough choice but i went with the power of the 335is instead of the redesigned 335i
heres the sticker
The 2011 335i is the n55 engine. 335is is n54.
I believe you went from n55 to n54 (which is a wise idea).